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Lyngsie G, Herzog SD, Hansen HCB, Persson P. Reactions between ferric oxyhydroxide mineral coatings and a dimethoxyhydroquinone: A source of hydroxyl radicals. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 949:175065. [PMID: 39067593 DOI: 10.1016/j.scitotenv.2024.175065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 07/05/2024] [Accepted: 07/24/2024] [Indexed: 07/30/2024]
Abstract
Quinones are organic molecules that facilitate electron-transfer reactions in terrestrial environments. The reduced forms, hydroquinones, are powerful reductants that can trigger non-enzymatic radical-based decomposition of organic matter and contaminants by simultaneous reduction of iron and oxygen. Iron oxides often occur as coatings on other minerals, thus our study investigated the reactions between the ferric oxyhydroxide (FeO(OH)) surface coatings on gibbsite (Al(OH)3) and 2,6-dimethoxy-1,4-hydroquinone (2,6-DMHQ). The main aim was to investigate the oxidation of 2,6-DMHQ and the generation ∙OH in the presence of O2 at low Fe concentrations in a novel setup that allows local structural characterization. The heterogeneous redox reactions between 2,6-DMHQ and the FeO(OH) coatings were studied at pH 5.0 as a function of the amount of Fe present on the gibbsite surfaces, including the effect of aging of the FeO(OH) coatings. The results showed that reactions between 2,6-DMHQ and FeO(OH) coated gibbsite under ambient conditions can generate substantial amounts of ·OH, comparable with amounts generated on pure ferrihydrite surfaces. The ·OH is the product of two sequential reactions: hydroquinone oxidation by O2 and degradation of the formed H2O2. The calculated rate constant of the former reaction is the same regardless of amount of FeO(OH) coating suggesting a surface catalytic process where 2,6-DMHQ is oxidized by O2 resulting in formation of H2O2. Subsequently, the observed induction period, the low Fe2+ (aq) concentrations in solution and the dependency of FeO(OH) coating amount influencing ·OH formation suggest that the pathway for ∙OH is through H2O2 decomposition by the surface sites on the FeO(OH) coating. Overall, this study shows that co-existence of oxygen, FeO(OH) and organic reductants, possibly secreted by soil microorganisms, creates favorable conditions for generation of ·OH contributing to decomposition of organic matter and organic pollutants in soil environments.
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Affiliation(s)
- Gry Lyngsie
- Department of Science and Environment, Roskilde University, DK-4000 Roskilde, Denmark.
| | - Simon D Herzog
- Department of Science and Environment, Roskilde University, DK-4000 Roskilde, Denmark
| | | | - Per Persson
- Centre for Environmental and Climate Science, Lund University, SE-223 62 Lund, Sweden
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2
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Martin FM, van der Heijden MGA. The mycorrhizal symbiosis: research frontiers in genomics, ecology, and agricultural application. THE NEW PHYTOLOGIST 2024; 242:1486-1506. [PMID: 38297461 DOI: 10.1111/nph.19541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 12/07/2023] [Indexed: 02/02/2024]
Abstract
Mycorrhizal symbioses between plants and fungi are vital for the soil structure, nutrient cycling, plant diversity, and ecosystem sustainability. More than 250 000 plant species are associated with mycorrhizal fungi. Recent advances in genomics and related approaches have revolutionized our understanding of the biology and ecology of mycorrhizal associations. The genomes of 250+ mycorrhizal fungi have been released and hundreds of genes that play pivotal roles in regulating symbiosis development and metabolism have been characterized. rDNA metabarcoding and metatranscriptomics provide novel insights into the ecological cues driving mycorrhizal communities and functions expressed by these associations, linking genes to ecological traits such as nutrient acquisition and soil organic matter decomposition. Here, we review genomic studies that have revealed genes involved in nutrient uptake and symbiosis development, and discuss adaptations that are fundamental to the evolution of mycorrhizal lifestyles. We also evaluated the ecosystem services provided by mycorrhizal networks and discuss how mycorrhizal symbioses hold promise for sustainable agriculture and forestry by enhancing nutrient acquisition and stress tolerance. Overall, unraveling the intricate dynamics of mycorrhizal symbioses is paramount for promoting ecological sustainability and addressing current pressing environmental concerns. This review ends with major frontiers for further research.
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Affiliation(s)
- Francis M Martin
- Université de Lorraine, INRAE, UMR IAM, Champenoux, 54280, France
- Institute of Applied Mycology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Marcel G A van der Heijden
- Department of Agroecology & Environment, Plant-Soil Interactions, Agroscope, Zürich, 8046, Switzerland
- Department of Plant and Microbial Biology, University of Zürich, Zürich, 8057, Switzerland
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3
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Auer L, Buée M, Fauchery L, Lombard V, Barry KW, Clum A, Copeland A, Daum C, Foster B, LaButti K, Singan V, Yoshinaga Y, Martineau C, Alfaro M, Castillo FJ, Imbert JB, Ramírez L, Castanera R, Pisabarro AG, Finlay R, Lindahl B, Olson A, Séguin A, Kohler A, Henrissat B, Grigoriev IV, Martin FM. Metatranscriptomics sheds light on the links between the functional traits of fungal guilds and ecological processes in forest soil ecosystems. THE NEW PHYTOLOGIST 2024; 242:1676-1690. [PMID: 38148573 DOI: 10.1111/nph.19471] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 11/23/2023] [Indexed: 12/28/2023]
Abstract
Soil fungi belonging to different functional guilds, such as saprotrophs, pathogens, and mycorrhizal symbionts, play key roles in forest ecosystems. To date, no study has compared the actual gene expression of these guilds in different forest soils. We used metatranscriptomics to study the competition for organic resources by these fungal groups in boreal, temperate, and Mediterranean forest soils. Using a dedicated mRNA annotation pipeline combined with the JGI MycoCosm database, we compared the transcripts of these three fungal guilds, targeting enzymes involved in C- and N mobilization from plant and microbial cell walls. Genes encoding enzymes involved in the degradation of plant cell walls were expressed at a higher level in saprotrophic fungi than in ectomycorrhizal and pathogenic fungi. However, ectomycorrhizal and saprotrophic fungi showed similarly high expression levels of genes encoding enzymes involved in fungal cell wall degradation. Transcripts for N-related transporters were more highly expressed in ectomycorrhizal fungi than in other groups. We showed that ectomycorrhizal and saprotrophic fungi compete for N in soil organic matter, suggesting that their interactions could decelerate C cycling. Metatranscriptomics provides a unique tool to test controversial ecological hypotheses and to better understand the underlying ecological processes involved in soil functioning and carbon stabilization.
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Affiliation(s)
- Lucas Auer
- Université de Lorraine, INRAE, UMR Interactions Arbres-Microorganismes, Nancy, F-54000, France
| | - Marc Buée
- Université de Lorraine, INRAE, UMR Interactions Arbres-Microorganismes, Nancy, F-54000, France
| | - Laure Fauchery
- Université de Lorraine, INRAE, UMR Interactions Arbres-Microorganismes, Nancy, F-54000, France
| | - Vincent Lombard
- Architecture et Fonction des Macromolécules Biologiques, CNRS and Aix-Marseille Université, Marseille, 13288, France
- INRAE, USC1408 Architecture et Fonction des Macromolécules Biologiques, Marseille, 13009, France
| | - Kerry W Barry
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Alicia Clum
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Alex Copeland
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Chris Daum
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Brian Foster
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kurt LaButti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Vasanth Singan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Yuko Yoshinaga
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Christine Martineau
- Laurentian Forestry Centre, Natural Resources Canada, Canadian Forest Service, Quebec, G1V4C7, QC, Canada
| | - Manuel Alfaro
- Institute for Multidisciplinary Research in Applied Biology (IMAB), Public University of Navarra (UPNA), Pamplona, 31006, Spain
| | - Federico J Castillo
- Institute for Multidisciplinary Research in Applied Biology (IMAB), Public University of Navarra (UPNA), Pamplona, 31006, Spain
| | - J Bosco Imbert
- Institute for Multidisciplinary Research in Applied Biology (IMAB), Public University of Navarra (UPNA), Pamplona, 31006, Spain
| | - Lucia Ramírez
- Institute for Multidisciplinary Research in Applied Biology (IMAB), Public University of Navarra (UPNA), Pamplona, 31006, Spain
| | - Raúl Castanera
- Institute for Multidisciplinary Research in Applied Biology (IMAB), Public University of Navarra (UPNA), Pamplona, 31006, Spain
| | - Antonio G Pisabarro
- Institute for Multidisciplinary Research in Applied Biology (IMAB), Public University of Navarra (UPNA), Pamplona, 31006, Spain
| | - Roger Finlay
- Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, Uppsala, 75007, Sweden
| | - Björn Lindahl
- Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, Uppsala, 75007, Sweden
| | - Ake Olson
- Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, Uppsala, 75007, Sweden
| | - Armand Séguin
- Laurentian Forestry Centre, Natural Resources Canada, Canadian Forest Service, Quebec, G1V4C7, QC, Canada
| | - Annegret Kohler
- Université de Lorraine, INRAE, UMR Interactions Arbres-Microorganismes, Nancy, F-54000, France
| | - Bernard Henrissat
- DTU Bioengineering, Denmarks Tekniske Universitet, Copenhagen, 2800, Denmark
- Department of Biological Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Francis M Martin
- Université de Lorraine, INRAE, UMR Interactions Arbres-Microorganismes, Nancy, F-54000, France
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De Quesada G, Xu J, Salmon Y, Lintunen A, Poque S, Himanen K, Heinonsalo J. The effect of ectomycorrhizal fungal exposure on nursery-raised Pinus sylvestris seedlings: plant transpiration under short-term drought, root morphology and plant biomass. TREE PHYSIOLOGY 2024; 44:tpae029. [PMID: 38470306 PMCID: PMC10990620 DOI: 10.1093/treephys/tpae029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 02/08/2024] [Accepted: 03/04/2024] [Indexed: 03/13/2024]
Abstract
Drought is a major environmental stressor that limits seedling growth. Several studies have found that some ectomycorrhizal fungi may increase the drought tolerance of nursery-raised seedlings. However, the precise role that different ectomycorrhizal fungi species play in drought tolerance remains unclear. We evaluated the transpiration rate of Pinus sylvestris seedlings under drought stress in greenhouse conditions by exposing seedlings to 10 ectomycorrhizal fungi species, with different functional traits (exploration type and hydrophobicity), and to 3 natural soil inoculums. We measured the transpiration and water potential of the seedlings during a 10-day drought period and a 14-day recovery period. We then analyzed their root morphology, stem, needle, root biomass and needle chlorophyll fluorescence. We showed that exposing seedlings to ectomycorrhizal fungi or soil inoculum had a positive effect on their transpiration rate during the driest period and through the recovery phase, leading to 2- to 3-fold higher transpiration rates compared with the nonexposed control seedlings. Seedlings exposed to medium-distance ectomycorrhizal fungi performed better than other exploration types under drought conditions, but ectomycorrhizal fungi hydrophobicity did not seem to affect the seedlings response to drought. No significant differences were observed in biomass accumulation and root morphology between the seedlings exposed to different ectomycorrhizal fungi species and the control. Our results highlight the positive and species-specific effect of ectomycorrhizal fungi exposure on drought tolerance in nursery-raised Scots pine seedlings. The studied ectomycorrhizal fungi functional traits may not be sufficient to predict the seedling response to drought stress, thus physiological studies across multiple species are needed to draw the correct conclusion. Our findings have potential practical implications for enhancing seedling drought tolerance in nursery plant production.
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Affiliation(s)
- Gonzalo De Quesada
- Department of Forest Sciences, Institute for Atmospheric and Earth System Research (INAR), Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, PO Box 27, FI-00014 Helsinki, Finland
| | - Jie Xu
- Department of Forest Sciences, Institute for Atmospheric and Earth System Research (INAR), Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, PO Box 27, FI-00014 Helsinki, Finland
| | - Yann Salmon
- Department of Forest Sciences, Institute for Atmospheric and Earth System Research (INAR), Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, PO Box 27, FI-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research (INAR), Faculty of Sciences, University of Helsinki, Gustaf Hällströmin katu 2, PO Box 64, FI-00014 Helsinki, Finland
| | - Anna Lintunen
- Department of Forest Sciences, Institute for Atmospheric and Earth System Research (INAR), Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, PO Box 27, FI-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research (INAR), Faculty of Sciences, University of Helsinki, Gustaf Hällströmin katu 2, PO Box 64, FI-00014 Helsinki, Finland
| | - Sylvain Poque
- National Plant Phenotyping Infrastructure, HiLIFE, Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, 00790 Helsinki, Finland
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Latokartanonkaari 7, 00790 Helsinki, Finland
| | - Kristiina Himanen
- National Plant Phenotyping Infrastructure, HiLIFE, Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, 00790 Helsinki, Finland
- Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, Biocenter Finland, University of Helsinki, Viikinkaari 1, 00790 Helsinki, Finland
| | - Jussi Heinonsalo
- Department of Forest Sciences, Institute for Atmospheric and Earth System Research (INAR), Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, PO Box 27, FI-00014 Helsinki, Finland
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5
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Hupperts SF, Islam KS, Gundale MJ, Kardol P, Sundqvist MK. Warming influences carbon and nitrogen assimilation between a widespread Ericaceous shrub and root-associated fungi. THE NEW PHYTOLOGIST 2024; 241:1062-1073. [PMID: 37950517 DOI: 10.1111/nph.19384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 10/19/2023] [Indexed: 11/12/2023]
Abstract
High-latitude ecosystems are warming faster than other biomes and are often dominated by a ground layer of Ericaceous shrubs, which can respond positively to warming. The carbon-for-nitrogen (C-for-N) exchange between Ericaceous shrubs and root-associated fungi may underlie shrub responses to warming, but has been understudied. In a glasshouse setting, we examined the effects of warming on the C-for-N exchange between the Ericaceous shrub Empetrum nigrum ssp. hermaphroditum and its root-associated fungi. We applied different 13 C and 15 N isotope labels, including a simple organic N form (glycine) and a complex organic N form (moss litter) and quantified their assimilation into soil, plant biomass, and root fungal biomass pools. We found that warming lowered the amount of 13 C partitioned to root-associated fungi per unit of glycine 15 N assimilated by E. nigrum, but only in the short term. By contrast, warming increased the amount of 13 C partitioned to root-associated fungi per unit of moss 15 N assimilated by E. nigrum. Our study suggests that climate warming affects the short-term exchange of C and N between a widespread Ericaceous shrub and root-associated fungi. Furthermore, while most isotope tracing studies use labile N sources, we demonstrate that a ubiquitous recalcitrant N source may produce contrasting results.
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Affiliation(s)
- Stefan F Hupperts
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
| | - Kazi Samiul Islam
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
| | - Michael J Gundale
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
| | - Paul Kardol
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences (SLU), Uppsala, 750 07, Sweden
| | - Maja K Sundqvist
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
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Yang H, Chen N, Wang Z, Liu J, Qin J, Zhu K, Jia H. Biochar-Associated Free Radicals Reduce Soil Bacterial Diversity: New Insight into Ecoenzymatic Stoichiometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20238-20248. [PMID: 37976412 DOI: 10.1021/acs.est.3c06864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
The toxicity of environmentally persistent free radicals (EPFRs), often generated during biochar production, on soil bacteria is still not truly reflected when considering the conditions in real soil. Herein, the influence of free radicals within biochar on soil bacteria was investigated from the perspectives of enzyme activity, community structure, and ecoenzymatic stoichiometry. Biochar addition enhanced the contents of EPFRs and derived hydroxyl radicals (•OH) in the soil, while it reduced bacterial alpha diversity by 5.06-35.44%. The results of redundancy analysis and inhibition experiments collectively demonstrated the key role of EPFRs and •OH in reducing the bacterial alpha diversity. Specifically, EPFRs and •OH increased the stoichiometric imbalance by promoting the release of dissolved organic carbon and ammonium N, thus aggravating the P limitation in soil. This was further confirmed by increased alkaline phosphatase activity from 702 to 874 nmol g-1 h-1. The P limitation induced by EPFRs and •OH decreased the bacterial alpha diversity, as evidenced by the negative correlation between P limitation and bacterial alpha diversity (r2 = -0.931 to -0.979, P < 0.01) and the structural equation model. The obtained results demonstrate a ubiquitous but previously overlooked mechanism for bacterial toxicity of biochar-associated free radicals, providing scientific guidance for safe utilization of biochar.
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Affiliation(s)
- Huiqiang Yang
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
- Key Laboratory of Low-carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Na Chen
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
- Key Laboratory of Low-carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Zhiqiang Wang
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
- Key Laboratory of Low-carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Jinbo Liu
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
- Key Laboratory of Low-carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Jianjun Qin
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
- Key Laboratory of Low-carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Kecheng Zhu
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
- Key Laboratory of Low-carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Hanzhong Jia
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
- Key Laboratory of Low-carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
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Castaño C, Hallin S, Egelkraut D, Lindahl BD, Olofsson J, Clemmensen KE. Contrasting plant-soil-microbial feedbacks stabilize vegetation types and uncouple topsoil C and N stocks across a subarctic-alpine landscape. THE NEW PHYTOLOGIST 2023; 238:2621-2633. [PMID: 36519258 DOI: 10.1111/nph.18679] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/02/2022] [Indexed: 05/19/2023]
Abstract
Global vegetation regimes vary in belowground carbon (C) and nitrogen (N) dynamics. However, disentangling large-scale climatic controls from the effects of intrinsic plant-soil-microbial feedbacks on belowground processes is challenging. In local gradients with similar pedo-climatic conditions, effects of plant-microbial feedbacks may be isolated from large-scale drivers. Across a subarctic-alpine mosaic of historic grazing fields and surrounding heath and birch forest, we evaluated whether vegetation-specific plant-microbial feedbacks involved contrasting N cycling characteristics and C and N stocks in the organic topsoil. We sequenced soil fungi, quantified functional genes within the inorganic N cycle, and measured 15 N natural abundance. In grassland soils, large N stocks and low C : N ratios associated with fungal saprotrophs, archaeal ammonia oxidizers, and bacteria capable of respiratory ammonification, indicating maintained inorganic N cycling a century after abandoned reindeer grazing. Toward forest and heath, increasing abundance of mycorrhizal fungi co-occurred with transition to organic N cycling. However, ectomycorrhizal fungal decomposers correlated with small soil N and C stocks in forest, while root-associated ascomycetes associated with small N but large C stocks in heath, uncoupling C and N storage across vegetation types. We propose that contrasting, positive plant-microbial feedbacks stabilize vegetation trajectories, resulting in diverging soil C : N ratios at the landscape scale.
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Affiliation(s)
- Carles Castaño
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, SE-75007, Uppsala, Sweden
| | - Sara Hallin
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, SE-75007, Uppsala, Sweden
| | - Dagmar Egelkraut
- Department of Biological Sciences, University of Bergen, 5006, Bergen, Norway
| | - Björn D Lindahl
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, SE-75007, Sweden
| | - Johan Olofsson
- Department of Ecology and Environmental Science, Umeå University, 90187, Umeå, Sweden
| | - Karina Engelbrecht Clemmensen
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, SE-75007, Uppsala, Sweden
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Niego AGT, Rapior S, Thongklang N, Raspé O, Hyde KD, Mortimer P. Reviewing the contributions of macrofungi to forest ecosystem processes and services. FUNGAL BIOL REV 2023. [DOI: 10.1016/j.fbr.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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9
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Zotti M, Bonanomi G, Saulino L, Allevato E, Saracino A, Mazzoleni S, Idbella M. Shifts of Leaf Litter-Induced Plant-Soil Feedback from Negative to Positive Driven by Ectomycorrhizal Symbiosis between Quercus ilex and Pisolithus arrhizus. Microorganisms 2023; 11:1394. [PMID: 37374896 DOI: 10.3390/microorganisms11061394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 05/18/2023] [Accepted: 05/23/2023] [Indexed: 06/29/2023] Open
Abstract
Ectomycorrhizas (ECM) are a common symbiotic association between fungi and various plant species in forest ecosystems, affecting community assemblages at the landscape level. ECMs benefit host plants by increasing the surface area for nutrient uptake, defending against pathogens, and decomposing organic matter in the soil. ECM-symbiotic seedlings are also known to perform better in conspecific soils than other species unable to carry the symbiosis, in a process referred to as plant-soil feedback (PSF). In this study, we tested the effects of different leaf litter amendments on ECM and non-ECM seedlings of Quercus ilex inoculated with Pisolithus arrhizus and how they altered the litter-induced PSF. Our experiment showed that the ECM symbiont induced a shift from negative PSF to positive PSF in Q. ilex seedlings by analysing plant and root growth parameters. However, non-ECM seedlings performed better than ECM seedlings in a no-litter condition, indicating an autotoxic effect when litter is present without ECM symbionts. Conversely, ECM seedlings with litter performed better at different decomposition stages, suggesting a possible role of the symbiosis of P. arrhizus and Q. ilex in recycling autotoxic compounds released from conspecific litter, transforming them into nutrients that are transferred to the plant host.
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Affiliation(s)
- Maurizio Zotti
- Department of Agricultural Sciences, University of Naples Federico II, Via Università, 100, 80055 Portici, Italy
| | - Giuliano Bonanomi
- Department of Agricultural Sciences, University of Naples Federico II, Via Università, 100, 80055 Portici, Italy
- Task Force on Microbiome Studies, University of Naples Federico II, 80138 Naples, Italy
| | - Luigi Saulino
- Department of Agricultural Sciences, University of Naples Federico II, Via Università, 100, 80055 Portici, Italy
| | - Emilia Allevato
- Department of Agricultural Sciences, University of Naples Federico II, Via Università, 100, 80055 Portici, Italy
| | - Antonio Saracino
- Department of Agricultural Sciences, University of Naples Federico II, Via Università, 100, 80055 Portici, Italy
| | - Stefano Mazzoleni
- Department of Agricultural Sciences, University of Naples Federico II, Via Università, 100, 80055 Portici, Italy
| | - Mohamed Idbella
- Department of Agricultural Sciences, University of Naples Federico II, Via Università, 100, 80055 Portici, Italy
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10
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Maillard F, Kohler A, Morin E, Hossann C, Miyauchi S, Ziegler-Devin I, Gérant D, Angeli N, Lipzen A, Keymanesh K, Johnson J, Barry K, Grigoriev IV, Martin FM, Buée M. Functional genomics gives new insights into the ectomycorrhizal degradation of chitin. THE NEW PHYTOLOGIST 2023; 238:845-858. [PMID: 36702619 DOI: 10.1111/nph.18773] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
Ectomycorrhizal (EcM) fungi play a crucial role in the mineral nitrogen (N) nutrition of their host trees. While it has been proposed that several EcM species also mobilize organic N, studies reporting the EcM ability to degrade N-containing polymers, such as chitin, remain scarce. Here, we assessed the capacity of a representative collection of 16 EcM species to acquire 15 N from 15 N-chitin. In addition, we combined genomics and transcriptomics to identify pathways involved in exogenous chitin degradation between these fungal strains. Boletus edulis, Imleria badia, Suillus luteus, and Hebeloma cylindrosporum efficiently mobilized N from exogenous chitin. EcM genomes primarily contained genes encoding for the direct hydrolysis of chitin. Further, we found a significant relationship between the capacity of EcM fungi to assimilate organic N from chitin and their genomic and transcriptomic potentials for chitin degradation. These findings demonstrate that certain EcM fungal species depolymerize chitin using hydrolytic mechanisms and that endochitinases, but not exochitinases, represent the enzymatic bottleneck of chitin degradation. Finally, this study shows that the degradation of exogenous chitin by EcM fungi might be a key functional trait of nutrient cycling in forests dominated by EcM fungi.
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Affiliation(s)
- François Maillard
- Université de Lorraine, INRAE, UMR 1136 Interactions Arbres-Microorganismes, 54280, Champenoux, France
| | - Annegret Kohler
- Université de Lorraine, INRAE, UMR 1136 Interactions Arbres-Microorganismes, 54280, Champenoux, France
| | - Emmanuelle Morin
- Université de Lorraine, INRAE, UMR 1136 Interactions Arbres-Microorganismes, 54280, Champenoux, France
| | - Christian Hossann
- Université de Lorraine, AgroParisTech, INRAE, SILVA, Silvatech, F-54000, Nancy, France
| | - Shingo Miyauchi
- Université de Lorraine, INRAE, UMR 1136 Interactions Arbres-Microorganismes, 54280, Champenoux, France
| | | | - Dominique Gérant
- Université de Lorraine, AgroParisTech, INRAE, UMR Silva, 54000, Nancy, France
| | - Nicolas Angeli
- Université de Lorraine, AgroParisTech, INRAE, SILVA, Silvatech, F-54000, Nancy, France
| | - Anna Lipzen
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Keykhosrow Keymanesh
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Jenifer Johnson
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Kerrie Barry
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Igor V Grigoriev
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Francis M Martin
- Université de Lorraine, INRAE, UMR 1136 Interactions Arbres-Microorganismes, 54280, Champenoux, France
| | - Marc Buée
- Université de Lorraine, INRAE, UMR 1136 Interactions Arbres-Microorganismes, 54280, Champenoux, France
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11
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Zhang M, Liu S, Chen M, Chen J, Cao X, Xu G, Xing H, Li F, Shi Z. The below-ground carbon and nitrogen cycling patterns of different mycorrhizal forests on the eastern Qinghai-Tibetan Plateau. PeerJ 2022; 10:e14028. [PMID: 36124133 PMCID: PMC9482363 DOI: 10.7717/peerj.14028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 08/16/2022] [Indexed: 01/19/2023] Open
Abstract
Mycorrhizal fungi can form symbiotic associations with tree species, which not only play an important role in plant survival and growth, but also in soil carbon (C) and nitrogen (N) cycling. However, the understanding of differences in soil C and N cycling patterns among forests with different mycorrhizal types is still incomplete. In order to determine the similarities and differences of soil C and N cycling patterns in different mycorrhizal forest types, three primary forests dominated by ectomycorrhizal (EcM), arbuscular mycorrhizal (AM) and ericoid mycorrhizal (ErM) trees respectively were studied on the eastern Qinghai-Tibetan Plateau. Indicators associated with soil C and N cycling, including leaf litter quality, soil C and N contents, soil C and N fluxes, and soil microbial biomass C and N contents were measured in each mycorrhizal type forest. The results showed that leaf litter quality was significantly lower with high C:N ratio and lignin: N ratio in ErM forest than that in AM and EcM forests. Soil CO2 flux (508.25 ± 65.51 mg m-2 h-1) in AM forest was significantly higher than that in EcM forest (387.18 ± 56.19 mg m-2 h-1) and ErM forest (177.87 ± 58.40 mg m-2 h-1). Furthermore, soil inorganic N content was higher in the AM forest than that in EcM and ErM forests. Soil net N mineralization rate (-0.02 ± 0.03 mg kg-1 d-1) was lower in ErM forest than that in EcM and AM forests. We speculated that AM and EcM forests were relatively characterized by rapid soil C cycling comparing to ErM forest. The soil N cycling in EcM and ErM forests were lower, implying they were 'organic' N nutrition patterns, and the pattern in ErM forest was more obvious.
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Affiliation(s)
- Miaomiao Zhang
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Shun Liu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Miao Chen
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Jian Chen
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Xiangwen Cao
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Gexi Xu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Hongshuang Xing
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Feifan Li
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China
| | - Zuomin Shi
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China,Miyaluo Research Station of Alpine Forest Ecosystem, Lixian County, Sichuan, China,Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China,Institute for Sustainable Plant Protection, National Research Council of Italy, Torino, Italy
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12
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Ward EB, Duguid MC, Kuebbing SE, Lendemer JC, Bradford MA. The functional role of ericoid mycorrhizal plants and fungi on carbon and nitrogen dynamics in forests. THE NEW PHYTOLOGIST 2022; 235:1701-1718. [PMID: 35704030 DOI: 10.1111/nph.18307] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
Ericoid mycorrhizal (ErM) shrubs commonly occur in forest understories and could therefore alter arbuscular (AM) and/or ectomycorrhizal (EcM) tree effects on soil carbon and nitrogen dynamics. Specifically, ErM fungi have extensive organic matter decay capabilities, and ErM plant and fungal tissues have high concentrations of secondary compounds that can form persistent complexes in the soil. Together, these traits could contribute to organic matter accumulation and inorganic nutrient limitation. These effects could also differ in AM- vs EcM-dominated stands at multiple scales within and among forest biomes by, for instance, altering fungal guild interactions. Most work on ErM effects in forests has been conducted in boreal forests dominated by EcM trees. However, ErM plants occur in c. 96, 69 and 29% of boreal, temperate and tropical forests, respectively. Within tropical montane forests, the effects of ErM plants could be particularly pronounced because their traits are more distinct from AM than EcM trees. Because ErM fungi can function as free-living saprotrophs, they could also be more resilient to forest disturbances than obligate symbionts. Further consideration of ErM effects within and among forest biomes could improve our understanding of how cooccurring mycorrhizal types interact to collectively affect soil carbon and nitrogen dynamics under changing conditions.
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Affiliation(s)
- Elisabeth B Ward
- The Forest School, Yale School of the Environment, Yale University, New Haven, CT, 06511, USA
- The New York Botanical Garden, The Bronx, NY, 10458, USA
| | - Marlyse C Duguid
- The Forest School, Yale School of the Environment, Yale University, New Haven, CT, 06511, USA
| | - Sara E Kuebbing
- The Forest School, Yale School of the Environment, Yale University, New Haven, CT, 06511, USA
| | | | - Mark A Bradford
- The Forest School, Yale School of the Environment, Yale University, New Haven, CT, 06511, USA
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13
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Wan D, Liu FF, Chen JB, Kappler A, Kuzyakov Y, Liu CQ, Yu GH. Microbial community mediates hydroxyl radical production in soil slurries by iron redox transformation. WATER RESEARCH 2022; 220:118689. [PMID: 35661513 DOI: 10.1016/j.watres.2022.118689] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/26/2022] [Accepted: 05/28/2022] [Indexed: 06/15/2023]
Abstract
The generation of reactive oxygen species (ROS) mediated by minerals and/or microorganisms plays a vital but underappreciated role in affecting carbon and nutrient cycles at soil-water interfaces. It is currently unknown which interactions between microbial communities and iron (Fe) minerals produce hydroxyl radical (HO•), which is the strongest oxidant among ROS. Using a series of well-controlled anoxic incubations of soil slurries, we demonstrated that interactions between microbial communities and Fe minerals synergistically drove HO• production (up to ∼100 nM after 21-day incubation). Microorganisms drove HO• generation in anoxic environments predominantly by modulating iron redox transformation that was more prominent than direct production of ROS by microorganisms. Among the microbial communities, Geobacter, Paucimonas, Rhodocyclaceae_K82, and Desulfotomaculum were the key genera strongly affecting HO• production. In manured soils, the former two species had higher abundances and were crucial for HO• production. In contrast, the latter two species were mainly abundant and important in soils with mineral fertilizers. Our study suggests that abundant highly reactive oxidant HO• can be generated in anoxic environments and the microbial community-mediated redox transformations of iron (oxyhydr)oxides may be responsible for the HO• production. These findings shed light on the microbial generation of HO• in fluctuating redox environments and on consequences for global C and nutrient cycling.
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Affiliation(s)
- Dan Wan
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China; School of Environmental Science and Engineering, Tiangong University, Tianjin 300387, China
| | - Fei-Fei Liu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jiu-Bin Chen
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Andreas Kappler
- Geomicrobiology, Center for Applied Geosciences, University of Tübingen, Tübingen 72076, Germany
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, University of Gӧttingen, Gӧttingen 37073, Germany; Agro-Technological Institute, Peoples Friendship University of Russia (RUDN University), Moscow 117198, Russia
| | - Cong-Qiang Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Guang-Hui Yu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China.
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14
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Chi ZL, Yu GH, Teng HH, Liu HG, Wang J, Liu CQ, Shen QR, Gadd GM. Molecular Trade-Offs between Lattice Oxygen and Oxygen Vacancy Drive Organic Pollutant Degradation in Fungal Biomineralized Exoskeletons. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8132-8141. [PMID: 35561278 DOI: 10.1021/acs.est.2c01388] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Fungal-mineral interactions can effectively alleviate cellular stress from organic pollutants, the production of which are expected to rapidly increase owing to the Earth moving into an unprecedented geological epoch, the Anthropocene. The underlying mechanisms that may enable fungi to combat organic pollution during fungal-mineral interactions remain unclear. Inspired by the natural fungal sporulation process, we demonstrate for the first time that fungal biomineralization triggers the formation of an ultrathin (hundreds of nanometers thick) exoskeleton, enriched in nanosized iron (oxyhydr)oxides and biomolecules, on the hyphae. Mapped biochemical composition of this coating at a subcellular scale via high spatial resolution (down to 50 nm) synchrotron radiation-based techniques confirmed aromatic C, C-N bonds, amide carbonyl, and iron (oxyhydr)oxides as the major components of the coatings. This nanobiohybrid system appeared to impart a strong (×2) biofunctionality for fungal degradation of bisphenol A through altering molecular-level trade-offs between lattice oxygen and oxygen vacancy. Together, fungal coatings could act as "artificial spores", which enable fungi to combat physical and chemical stresses in natural environments, providing crucial insights into fungal biomineralization and coevolution of the Earth's lithosphere and biosphere.
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Affiliation(s)
- Zhi-Lai Chi
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
- College of Resources & Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Guang-Hui Yu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - H Henry Teng
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
- Department of Chemistry, George Washington University, Washington, District of Columbia 20006, United States
| | - Hai-Gang Liu
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Jian Wang
- Canadian Light Source Inc., University of Saskatchewan, 44 Innovation Boulevard, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - Cong-Qiang Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Qi-Rong Shen
- College of Resources & Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Geoffrey Michael Gadd
- Geomicrobiology Group, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Oil and Gas Pollution Control, College of Chemical Engineering and Environment, China University of Petroleum, Beijing 102249, China
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15
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Looney B, Miyauchi S, Morin E, Drula E, Courty PE, Kohler A, Kuo A, LaButti K, Pangilinan J, Lipzen A, Riley R, Andreopoulos W, He G, Johnson J, Nolan M, Tritt A, Barry KW, Grigoriev IV, Nagy LG, Hibbett D, Henrissat B, Matheny PB, Labbé J, Martin FM. Evolutionary transition to the ectomycorrhizal habit in the genomes of a hyperdiverse lineage of mushroom-forming fungi. THE NEW PHYTOLOGIST 2022; 233:2294-2309. [PMID: 34861049 DOI: 10.1111/nph.17892] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 11/24/2021] [Indexed: 06/13/2023]
Abstract
The ectomycorrhizal (ECM) symbiosis has independently evolved from diverse types of saprotrophic ancestors. In this study, we seek to identify genomic signatures of the transition to the ECM habit within the hyperdiverse Russulaceae. We present comparative analyses of the genomic architecture and the total and secreted gene repertoires of 18 species across the order Russulales, of which 13 are newly sequenced, including a representative of a saprotrophic member of Russulaceae, Gloeopeniophorella convolvens. The genomes of ECM Russulaceae are characterized by a loss of genes for plant cell wall-degrading enzymes (PCWDEs), an expansion of genome size through increased transposable element (TE) content, a reduction in secondary metabolism clusters, and an association of small secreted proteins (SSPs) with TE 'nests', or dense aggregations of TEs. Some PCWDEs have been retained or even expanded, mostly in a species-specific manner. The genome of G. convolvens possesses some characteristics of ECM genomes (e.g. loss of some PCWDEs, TE expansion, reduction in secondary metabolism clusters). Functional specialization in ECM decomposition may drive diversification. Accelerated gene evolution predates the evolution of the ECM habit, indicating that changes in genome architecture and gene content may be necessary to prime the evolutionary switch.
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Affiliation(s)
- Brian Looney
- Department of Biology, Clark University, Worcester, MA, 01610, USA
| | - Shingo Miyauchi
- UMR Interactions Arbres/Microorganismes, Centre INRAE Grand Est-Nancy, INRAE, Université de Lorraine, Champenoux, 54000, France
| | - Emmanuelle Morin
- UMR Interactions Arbres/Microorganismes, Centre INRAE Grand Est-Nancy, INRAE, Université de Lorraine, Champenoux, 54000, France
| | - Elodie Drula
- Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille Univ., Marseille, 13009, France
- USC1408 Architecture et Fonction des Macromolécules Biologiques (AFMB), INRAE, Marseille, 13009, France
| | - Pierre Emmanuel Courty
- Agroécologie, AgroSup Dijon, CNRS, INRAE, Université de Bourgogne, Université de Bourgogne Franche- Comté, Dijon, 25000, France
| | - Annegret Kohler
- UMR Interactions Arbres/Microorganismes, Centre INRAE Grand Est-Nancy, INRAE, Université de Lorraine, Champenoux, 54000, France
| | - Alan Kuo
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Kurt LaButti
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Jasmyn Pangilinan
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Anna Lipzen
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Robert Riley
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - William Andreopoulos
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Guifen He
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Jenifer Johnson
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Matt Nolan
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Andrew Tritt
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Kerrie W Barry
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
| | - Igor V Grigoriev
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - László G Nagy
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre, Szeged, 6726, Hungary
- Department of Plant Anatomy, Institute of Biology, Eötvös Loránd University, Budapest, 1053, Hungary
| | - David Hibbett
- Department of Biology, Clark University, Worcester, MA, 01610, USA
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille Univ., Marseille, 13009, France
- Department of Biological Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - P Brandon Matheny
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, 37996, USA
| | - Jesse Labbé
- Biosciences Division, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, TN, 37830, USA
| | - Francis M Martin
- UMR Interactions Arbres/Microorganismes, Centre INRAE Grand Est-Nancy, INRAE, Université de Lorraine, Champenoux, 54000, France
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China
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16
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Rivera Pérez CA, Janz D, Schneider D, Daniel R, Polle A. Transcriptional Landscape of Ectomycorrhizal Fungi and Their Host Provides Insight into N Uptake from Forest Soil. mSystems 2022; 7:e0095721. [PMID: 35089084 PMCID: PMC8725588 DOI: 10.1128/msystems.00957-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 11/29/2021] [Indexed: 01/05/2023] Open
Abstract
Mineral nitrogen (N) is a major nutrient showing strong fluctuations in the environment due to anthropogenic activities. The acquisition and translocation of N to forest trees are achieved mainly by highly diverse ectomycorrhizal fungi (EMF) living in symbioses with their host roots. Here, we examined colonized root tips to characterize the entire root-associated fungal community by DNA metabarcoding-Illumina sequencing of the fungal internal transcribed spacer 2 (ITS2) molecular marker and used RNA sequencing to target metabolically active fungi and the plant transcriptome after N application. The study was conducted with beech (Fagus sylvatica L.), a dominant tree species in central Europe, grown in native forest soil. We demonstrate strong enrichment of 15N from nitrate or ammonium in the ectomycorrhizal roots by stable-isotope labeling. The relative abundance of the EMF members in the fungal community was correlated with their transcriptional abundances. The fungal metatranscriptome covered Kyoto Encyclopedia of Genes and Genomes (KEGG) and Eukaryotic Orthologous Groups (KOG) categories similar to those of model fungi and did not reveal significant changes related to N metabolization but revealed species-specific transcription patterns, supporting trait stability. In contrast to the resistance of the fungal metatranscriptome, the transcriptome of the host exhibited dedicated nitrate- or ammonium-responsive changes with the upregulation of transporters and enzymes required for nitrate reduction and a drastic enhancement of glutamine synthetase transcript levels, indicating the channeling of ammonium into the pathway for plant protein biosynthesis. Our results support that naturally assembled fungal communities living in association with the tree roots buffer nutritional signals in their own metabolism but do not shield plants from high environmental N levels. IMPORTANCE Although EMF are well known for their role in supporting tree N nutrition, the molecular mechanisms underlying N flux from the soil solution into the host through the ectomycorrhizal pathway remain widely unknown. Furthermore, ammonium and nitrate availability in the soil solution is subject to frequent oscillations that create a dynamic environment for the tree roots and associated microbes during N acquisition. Therefore, it is important to understand how root-associated mycobiomes and the tree roots handle these fluctuations. We studied the responses of the symbiotic partners by screening their transcriptomes after a sudden environmental flux of nitrate or ammonium. We show that the fungi and the host respond asynchronously, with the fungi displaying resistance to increased nitrate or ammonium and the host dynamically metabolizing the supplied N sources. This study provides insights into the molecular mechanisms of the symbiotic partners operating under N enrichment in a multidimensional symbiotic system.
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Affiliation(s)
- Carmen Alicia Rivera Pérez
- Forest Botany and Tree Physiology, Büsgen Institute, Georg-August University of Göttingen, Göttingen, Germany
| | - Dennis Janz
- Forest Botany and Tree Physiology, Büsgen Institute, Georg-August University of Göttingen, Göttingen, Germany
| | - Dominik Schneider
- Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Göttingen, Germany
- Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Göttingen, Germany
| | - Rolf Daniel
- Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Göttingen, Germany
- Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Göttingen, Germany
| | - Andrea Polle
- Forest Botany and Tree Physiology, Büsgen Institute, Georg-August University of Göttingen, Göttingen, Germany
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17
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Chi ZL, Yu GH, Kappler A, Liu CQ, Gadd GM. Fungal-Mineral Interactions Modulating Intrinsic Peroxidase-like Activity of Iron Nanoparticles: Implications for the Biogeochemical Cycles of Nutrient Elements and Attenuation of Contaminants. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:672-680. [PMID: 34905360 DOI: 10.1021/acs.est.1c06596] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Fungal-mediated extracellular reactive oxygen species (ROS) are essential for biogeochemical cycles of carbon, nitrogen, and contaminants in terrestrial environments. These ROS levels may be modulated by iron nanoparticles that possess intrinsic peroxidase (POD)-like activity (nanozymes). However, it remains largely undescribed how fungi modulate the POD-like activity of the iron nanoparticles with various crystallinities and crystal facets. Using well-controlled fungal-mineral cultivation experiments, here, we showed that fungi possessed a robust defect engineering strategy to modulate the POD-like activity of the attached iron minerals by decreasing the catalytic activity of poorly ordered ferrihydrite but enhancing that of well-crystallized hematite. The dynamics of POD-like activity were found to reside in molecular trade-offs between lattice oxygen and oxygen vacancies in the iron nanoparticles, which may be located in a cytoprotective fungal exoskeleton. Together, our findings unveil coupled POD-like activity and oxygen redox dynamics during fungal-mineral interactions, which increase the understanding of the catalytic mechanisms of POD-like nanozymes and microbial-mediated biogeochemical cycles of nutrient elements as well as the attenuation of contaminants in terrestrial environments.
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Affiliation(s)
- Zhi-Lai Chi
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
- Jiangsu Provincial Key Laboratory for Organic Solid Waste Utilization, College of Resource & Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Guang-Hui Yu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
| | - Andreas Kappler
- Geomicrobiology, Centre for Applied Geosciences, University of Tübingen, Tübingen 72076, Germany
| | - Cong-Qiang Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
| | - Geoffrey Michael Gadd
- Geomicrobiology Group, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Oil and Gas Pollution Control, College of Chemical Engineering and Environment, China University of Petroleum, Beijing 102249, China
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18
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Lebreton A, Zeng Q, Miyauchi S, Kohler A, Dai YC, Martin FM. Evolution of the Mode of Nutrition in Symbiotic and Saprotrophic Fungi in Forest Ecosystems. ANNUAL REVIEW OF ECOLOGY, EVOLUTION, AND SYSTEMATICS 2021. [DOI: 10.1146/annurev-ecolsys-012021-114902] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In this review, we highlight the main insights that have been gathered from recent developments using large-scale genomics of fungal saprotrophs and symbiotrophs (including ectomycorrhizal and orchid and ericoid mycorrhizal fungi) inhabiting forest ecosystems. After assessing the goals and motivations underlying our approach, we explore our current understanding of the limits and future potential of using genomics to understand the ecological roles of these forest fungi. Comparative genomics unraveled the molecular machineries involved in lignocellulose decomposition in wood decayers, soil and litter saprotrophs, and mycorrhizal symbionts. They also showed that transitions from saprotrophy to mutualism entailed widespread losses of lignocellulose-degrading enzymes; diversification of novel, lineage-specific symbiosis-induced genes; and convergent evolution of genetic innovations that facilitate the accommodationof mutualistic symbionts within their plant hosts. We also identify the major questions that remain unanswered and propose new avenues of genome-based research to understand the role of soil fungi in sustainable forest ecosystems.
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Affiliation(s)
- Annie Lebreton
- Beijing Advanced Innovation Centre for Tree Breeding by Molecular Design (BAIC-TBMD), Institute of Microbiology, Beijing Forestry University, Beijing, China 100083
- Université de Lorraine, Unité Mixte de Recherche (UMR) Interactions Arbres/Microorganismes, Centre INRAE (Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement) Grand Est-Nancy, INRAE, 54280 Champenoux, France
| | - Qingchao Zeng
- Beijing Advanced Innovation Centre for Tree Breeding by Molecular Design (BAIC-TBMD), Institute of Microbiology, Beijing Forestry University, Beijing, China 100083
| | - Shingo Miyauchi
- Max Planck Institute for Plant Breeding Research, Department of Plant–Microbe Interactions, Köln, Germany, D-50829
| | - Annegret Kohler
- Université de Lorraine, Unité Mixte de Recherche (UMR) Interactions Arbres/Microorganismes, Centre INRAE (Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement) Grand Est-Nancy, INRAE, 54280 Champenoux, France
| | - Yu-Cheng Dai
- Beijing Advanced Innovation Centre for Tree Breeding by Molecular Design (BAIC-TBMD), Institute of Microbiology, Beijing Forestry University, Beijing, China 100083
| | - Francis M. Martin
- Beijing Advanced Innovation Centre for Tree Breeding by Molecular Design (BAIC-TBMD), Institute of Microbiology, Beijing Forestry University, Beijing, China 100083
- Université de Lorraine, Unité Mixte de Recherche (UMR) Interactions Arbres/Microorganismes, Centre INRAE (Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement) Grand Est-Nancy, INRAE, 54280 Champenoux, France
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19
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Quo vadis: signaling molecules and small secreted proteins from mycorrhizal fungi at the early stage of mycorrhiza formation. Symbiosis 2021. [DOI: 10.1007/s13199-021-00793-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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20
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Wang T, Persson P, Tunlid A. A widespread mechanism in ectomycorrhizal fungi to access nitrogen from mineral-associated proteins. Environ Microbiol 2021; 23:5837-5849. [PMID: 33891367 DOI: 10.1111/1462-2920.15539] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 11/27/2022]
Abstract
A large fraction of nitrogen (N) in forest soils is present in mineral-associated proteinaceous compounds. The strong association between proteins and minerals limits microbial accessibility to this source, which is a relatively stable reservoir of soil N. We have shown that the ectomycorrhizal (ECM) fungus Paxillus involutus can acquire N from iron oxide-associated proteins. Using tightly controlled isotopic, spectroscopic and chromatographic experiments, we demonstrated that the capacity to access N from iron oxide-associated bovine serum albumin (BSA) is shared with the ECM fungi Hebeloma cylindrosporum and Piloderma olivaceum. Despite differences in evolutionary history, growth rates, exploration types and the decomposition mechanisms of organic matter, their N acquisition mechanisms were similar to those described for P. involutus. The fungi released N from mineral-associated BSA by direct action of extracellular aspartic proteases on the mineral-associated BSA, without initial desorption of the protein. Hydrolysis was suppressed by the adsorption of proteases to minerals, but this adverse effect was counteracted by the secretion of compounds that conditioned the mineral surface. These data suggest that the enzymatic exudate-driven mechanism to access N from mineral-associated proteins is found in ECM fungi of multiple lineages and exploration types.
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Affiliation(s)
- Tao Wang
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, Lund, SE-223 62, Sweden.,CAS Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Per Persson
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, Lund, SE-223 62, Sweden.,Centre for Environmental and Climate Research (CEC), Lund University, Ecology Building, Lund, SE-223 62, Sweden
| | - Anders Tunlid
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, Lund, SE-223 62, Sweden
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21
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Lofgren LA, Nguyen NH, Vilgalys R, Ruytinx J, Liao HL, Branco S, Kuo A, LaButti K, Lipzen A, Andreopoulos W, Pangilinan J, Riley R, Hundley H, Na H, Barry K, Grigoriev IV, Stajich JE, Kennedy PG. Comparative genomics reveals dynamic genome evolution in host specialist ectomycorrhizal fungi. THE NEW PHYTOLOGIST 2021; 230:774-792. [PMID: 33355923 PMCID: PMC7969408 DOI: 10.1111/nph.17160] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/16/2020] [Indexed: 05/24/2023]
Abstract
While there has been significant progress characterizing the 'symbiotic toolkit' of ectomycorrhizal (ECM) fungi, how host specificity may be encoded into ECM fungal genomes remains poorly understood. We conducted a comparative genomic analysis of ECM fungal host specialists and generalists, focusing on the specialist genus Suillus. Global analyses of genome dynamics across 46 species were assessed, along with targeted analyses of three classes of molecules previously identified as important determinants of host specificity: small secreted proteins (SSPs), secondary metabolites (SMs) and G-protein coupled receptors (GPCRs). Relative to other ECM fungi, including other host specialists, Suillus had highly dynamic genomes including numerous rapidly evolving gene families and many domain expansions and contractions. Targeted analyses supported a role for SMs but not SSPs or GPCRs in Suillus host specificity. Phylogenomic-based ancestral state reconstruction identified Larix as the ancestral host of Suillus, with multiple independent switches between white and red pine hosts. These results suggest that like other defining characteristics of the ECM lifestyle, host specificity is a dynamic process at the genome level. In the case of Suillus, both SMs and pathways involved in the deactivation of reactive oxygen species appear to be strongly associated with enhanced host specificity.
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Affiliation(s)
- Lotus A Lofgren
- Department of Microbiology and Plant Pathology, University of California Riverside, Riverside, CA, 92507, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
| | - Nhu H Nguyen
- Department of Tropical Plant and Soil Science, University of Hawaii, Manoa, HI, 96822, USA
| | - Rytas Vilgalys
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Joske Ruytinx
- Research group Microbiology, Department of Bio-engineering Sciences, Vrije Universiteit Brussel, Brussel, BE1500, Belgium
| | - Hui-Ling Liao
- Department of Soil Microbial Ecology, University of Florida, Quincy, FL, 32351, USA
| | - Sara Branco
- Department of Integrative Biology, University of Colorado Denver, Denver, CO, 80204, USA
| | - Alan Kuo
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kurt LaButti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - William Andreopoulos
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Jasmyn Pangilinan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Robert Riley
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Hope Hundley
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Hyunsoo Na
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, University of California Riverside, Riverside, CA, 92507, USA
| | - Peter G Kennedy
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
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22
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Shah F, Gressler M, Nehzati S, Op De Beeck M, Gentile L, Hoffmeister D, Persson P, Tunlid A. Secretion of Iron(III)-Reducing Metabolites during Protein Acquisition by the Ectomycorrhizal Fungus Paxillus involutus. Microorganisms 2020; 9:E35. [PMID: 33374225 PMCID: PMC7824621 DOI: 10.3390/microorganisms9010035] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/21/2020] [Accepted: 12/21/2020] [Indexed: 11/17/2022] Open
Abstract
The ectomycorrhizal fungus Paxillus involutus decomposes proteins using a two-step mechanism, including oxidation and proteolysis. Oxidation involves the action of extracellular hydroxyl radicals (•OH) generated by the Fenton reaction. This reaction requires the presence of iron(II). Here, we monitored the speciation of extracellular iron and the secretion of iron(III)-reducing metabolites during the decomposition of proteins by P. involutus. X-ray absorption spectroscopy showed that extracellular iron was mainly present as solid iron(III) phosphates and oxides. Within 1 to 2 days, these compounds were reductively dissolved, and iron(II) complexes were formed, which remained in the medium throughout the incubation. HPLC and mass spectrometry detected five extracellular iron(III)-reducing metabolites. Four of them were also secreted when the fungus grew on a medium containing ammonium as the sole nitrogen source. NMR identified the unique iron(III)-reductant as the diarylcyclopentenone involutin. Involutin was produced from day 2, just before the elevated •OH production, preceding the oxidation of BSA. The other, not yet fully characterized iron(III)-reductants likely participate in the rapid reduction and dissolution of solid iron(III) complexes observed on day one. The production of these metabolites is induced by other environmental cues than for involutin, suggesting that they play a role beyond the Fenton chemistry associated with protein oxidation.
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Affiliation(s)
- Firoz Shah
- Microbial Ecology Group, Department of Biology, Lund University, 223 62 Lund, Sweden; (F.S.); (S.N.); (M.O.D.B.); (L.G.)
| | - Markus Gressler
- Department of Pharmaceutical Microbiology at the Hans Knöll Institute, Friedrich-Schiller-Universität, 07747 Jena, Germany; (M.G.); (D.H.)
| | - Susan Nehzati
- Microbial Ecology Group, Department of Biology, Lund University, 223 62 Lund, Sweden; (F.S.); (S.N.); (M.O.D.B.); (L.G.)
- MAX IV Laboratory, Lund University, 221 00 Lund, Sweden
| | - Michiel Op De Beeck
- Microbial Ecology Group, Department of Biology, Lund University, 223 62 Lund, Sweden; (F.S.); (S.N.); (M.O.D.B.); (L.G.)
| | - Luigi Gentile
- Microbial Ecology Group, Department of Biology, Lund University, 223 62 Lund, Sweden; (F.S.); (S.N.); (M.O.D.B.); (L.G.)
| | - Dirk Hoffmeister
- Department of Pharmaceutical Microbiology at the Hans Knöll Institute, Friedrich-Schiller-Universität, 07747 Jena, Germany; (M.G.); (D.H.)
| | - Per Persson
- Centre for Environmental and Climate Research (CEC), Lund University, 223 62 Lund, Sweden;
| | - Anders Tunlid
- Microbial Ecology Group, Department of Biology, Lund University, 223 62 Lund, Sweden; (F.S.); (S.N.); (M.O.D.B.); (L.G.)
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23
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Peltoniemi K, Adamczyk S, Fritze H, Minkkinen K, Pennanen T, Penttilä T, Sarjala T, Laiho R. Site fertility and soil water-table level affect fungal biomass production and community composition in boreal peatland forests. Environ Microbiol 2020; 23:5733-5749. [PMID: 33350006 DOI: 10.1111/1462-2920.15368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/15/2020] [Accepted: 12/19/2020] [Indexed: 11/28/2022]
Abstract
A substantial amount of below-ground carbon (C) is suggested to be associated with fungi, which may significantly affect the soil C balance in forested ecosystems. Ergosterol from in-growth mesh bags and litterbags was used to estimate fungal biomass production and community composition in drained peatland forests with differing fertility. Extramatrical mycelia (EMM) biomass production was generally higher in the nutrient-poor site, increased with deeper water table level and decreased along the length of the recovery time. EMM biomass production was of the same magnitude as in mineral-soil forests. Saprotrophic fungal biomass production was higher in the nutrient-rich site. Both ectomycorrhizal (ECM) and saprotrophic fungal community composition changed according to site fertility and water table level. ECM fungal community composition with different exploration types may explain the differences in fungal biomass production between peatland forests. Melanin-rich Hyaloscypha may indicate decreased turnover of biomass in nutrient-rich young peatland forest. Genera Lactarius and Laccaria may be important in nutrient rich and Piloderma in the nutrient-poor conditions, respectively. Furthermore, Paxillus involutus and Cortinarius sp. may be important generalists in all sites and responsible for EMM biomass production during the first summer months. Saprotrophs showed a functionally more diverse fungal community in the nutrient-rich site.
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Affiliation(s)
- Krista Peltoniemi
- Natural Resources Institute Finland (LUKE), Natural Resources, Latokartanonkaari 9, Helsinki, FI-00790, Finland
| | - Sylwia Adamczyk
- Natural Resources Institute Finland (LUKE), Natural Resources, Latokartanonkaari 9, Helsinki, FI-00790, Finland
| | - Hannu Fritze
- Natural Resources Institute Finland (LUKE), Natural Resources, Latokartanonkaari 9, Helsinki, FI-00790, Finland
| | - Kari Minkkinen
- Department of Forest Sciences, University of Helsinki, Latokartanonkaari 7, Helsinki, FI-00790, Finland
| | - Taina Pennanen
- Natural Resources Institute Finland (LUKE), Natural Resources, Latokartanonkaari 9, Helsinki, FI-00790, Finland
| | - Timo Penttilä
- Natural Resources Institute Finland (LUKE), Natural Resources, Latokartanonkaari 9, Helsinki, FI-00790, Finland
| | - Tytti Sarjala
- Natural Resources Institute Finland (LUKE), Production Systems, Kaironiementie 15, Parkano, FI-39700, Finland
| | - Raija Laiho
- Natural Resources Institute Finland (LUKE), Natural Resources, Latokartanonkaari 9, Helsinki, FI-00790, Finland
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24
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Photocatalytic activity of spinel ferrites CoxFe3−xO4 (0.25 < x < 1) obtained by treatment contact low-temperature non-equilibrium plasma. APPLIED NANOSCIENCE 2020. [DOI: 10.1007/s13204-020-01344-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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25
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Large-scale genome sequencing of mycorrhizal fungi provides insights into the early evolution of symbiotic traits. Nat Commun 2020; 11:5125. [PMID: 33046698 PMCID: PMC7550596 DOI: 10.1038/s41467-020-18795-w] [Citation(s) in RCA: 189] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 09/16/2020] [Indexed: 12/25/2022] Open
Abstract
Mycorrhizal fungi are mutualists that play crucial roles in nutrient acquisition in terrestrial ecosystems. Mycorrhizal symbioses arose repeatedly across multiple lineages of Mucoromycotina, Ascomycota, and Basidiomycota. Considerable variation exists in the capacity of mycorrhizal fungi to acquire carbon from soil organic matter. Here, we present a combined analysis of 135 fungal genomes from 73 saprotrophic, endophytic and pathogenic species, and 62 mycorrhizal species, including 29 new mycorrhizal genomes. This study samples ecologically dominant fungal guilds for which there were previously no symbiotic genomes available, including ectomycorrhizal Russulales, Thelephorales and Cantharellales. Our analyses show that transitions from saprotrophy to symbiosis involve (1) widespread losses of degrading enzymes acting on lignin and cellulose, (2) co-option of genes present in saprotrophic ancestors to fulfill new symbiotic functions, (3) diversification of novel, lineage-specific symbiosis-induced genes, (4) proliferation of transposable elements and (5) divergent genetic innovations underlying the convergent origins of the ectomycorrhizal guild. Mycorrhizal symbioses have evolved repeatedly in diverse fungal lineages. A large phylogenomic analysis sheds light on genomic changes associated with transitions from saprotrophy to symbiosis, including divergent genetic innovations underlying the convergent origins of the ectomycorrhizal guild.
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26
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Wang T, Tian Z, Tunlid A, Persson P. Nitrogen acquisition from mineral-associated proteins by an ectomycorrhizal fungus. THE NEW PHYTOLOGIST 2020; 228:697-711. [PMID: 32279319 DOI: 10.1111/nph.16596] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 03/29/2020] [Indexed: 05/07/2023]
Abstract
In nitrogen (N)-limited boreal forests, trees depend on the decomposing activity of their ectomycorrhizal (ECM) fungal symbionts to access soil N. A large fraction of this N exists as proteinaceous compounds associated with mineral particles. However, it is not known if ECM fungi can access these mineral-associated proteins; accordingly, possible acquisition mechanisms have not been investigated. With tightly controlled isotopic, spectroscopic, and chromatographic experiments, we quantified and analyzed the mechanisms of N acquisition from iron oxide mineral-associated proteins by Paxillus involutus, a widespread ECM fungus in boreal forests. The fungus acquired N from the mineral-associated proteins. The collective results indicated a proteolytic mechanism involving formation of the crucial enzyme-substrate complexes at the mineral surfaces. Hence, the enzymes hydrolyzed the mineral-associated proteins without initial desorption of the proteins. The proteolytic activity was suppressed by adsorption of proteases to the mineral particles. This process was counteracted by fungal secretion of mineral-surface-reactive compounds that decreased the protease-mineral interactions and thereby promoted the formation of enzyme-substrate complexes. The ability of ECM fungi to simultaneously generate extracellular proteases and surface-reactive metabolites suggests that they can play an important role in unlocking the large N pool of mineral-associated proteins to trees in boreal forests.
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Affiliation(s)
- Tao Wang
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden
| | - Zhaomo Tian
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden
- Centre for Environmental and Climate Research (CEC), Lund University, Ecology Building, SE-223 62, Lund, Sweden
| | - Anders Tunlid
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden
| | - Per Persson
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden
- Centre for Environmental and Climate Research (CEC), Lund University, Ecology Building, SE-223 62, Lund, Sweden
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27
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Chi ZL, Zhao XY, Chen YL, Hao JL, Yu GH, Goodman BA, Gadd GM. Intrinsic enzyme-like activity of magnetite particles is enhanced by cultivation with Trichoderma guizhouense. Environ Microbiol 2020; 23:893-907. [PMID: 32783346 DOI: 10.1111/1462-2920.15193] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 08/09/2020] [Indexed: 11/30/2022]
Abstract
Fungal-mineral interactions can produce large amounts of biogenic nano-size (~ 1-100 nm) minerals, yet their influence on fungal physiology and growth remains largely unexplored. Using Trichoderma guizhouense NJAU4742 and magnetite (Mt) as a model fungus and mineral system, we have shown for the first time that biogenic Mt nanoparticles formed during fungal-mineral cultivation exhibit intrinsic peroxidase-like activity. Specifically, the average peroxidase-like activity of Mt nanoparticles after 72 h cultivation was ~ 2.4 times higher than that of the original Mt. Evidence from high resolution X-ray photoelectron spectroscopy analyses indicated that the unique properties of magnetite nanoparticles largely stemmed from their high proportion of surface non-lattice oxygen, through occupying surface oxygen-vacant sites, rather than Fe redox chemistry, which challenges conventional Fenton reaction theories that assume iron to be the sole redox-active centre. Nanoscale secondary ion mass spectrometry with a resolution down to 50 nm demonstrated that a thin (< 1 μm) oxygen-film was present on the surface of fungal hyphae. Furthermore, synchrotron radiation-based micro-FTIR spectra revealed that surface oxygen groups corresponded mainly to organic OH, mineral OH and carbonyl groups. Together, these findings highlight an important, but unrecognized, catalytic activity of mineral nanoparticles produced by fungal-mineral interactions and contribute substantially to our understanding of mineral nanoparticles in natural ecosystems.
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Affiliation(s)
- Zhi-Lai Chi
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, College of Resource & Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiang-Yang Zhao
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, College of Resource & Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ya-Ling Chen
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, College of Resource & Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.,Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Jia-Long Hao
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Guang-Hui Yu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, College of Resource & Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.,Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Bernard A Goodman
- College of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Geoffrey Michael Gadd
- Geomicrobiology Group, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK.,State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Oil and Gas Pollution Control, College of Chemical Engineering and Environment, China University of Petroleum, Beijing, 102249, China
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28
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Thoen E, Harder CB, Kauserud H, Botnen SS, Vik U, Taylor AFS, Menkis A, Skrede I. In vitro evidence of root colonization suggests ecological versatility in the genus Mycena. THE NEW PHYTOLOGIST 2020; 227:601-612. [PMID: 32171021 DOI: 10.1111/nph.16545] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 03/03/2020] [Indexed: 06/10/2023]
Abstract
The root-associated habit has evolved on numerous occasions in different fungal lineages, suggesting a strong evolutionary pressure for saprotrophic fungi to switch to symbiotic associations with plants. Species within the ubiquitous, saprotrophic genus Mycena are frequently major components in molecular studies of root-associated fungal communities, suggesting that an evaluation of their trophic status is warranted. Here, we report on interactions between a range of Mycena species and the plant Betula pendula. In all, 17 Mycena species were inoculated onto B. pendula seedlings. Physical interactions between hyphae and fine roots were examined using differential staining and fluorescence microscopy. Physiological interactions were investigated using 14 C and 32 P to show potential transfer between symbionts. All Mycena species associated closely with fine roots, showing hyphal penetration into the roots, which in some cases were intracellular. Seven species formed mantle-like structures around root tips, but none formed a Hartig net. Mycena pura and Mycena galopus both enhanced seedling growth, with M. pura showing significant transfer of 32 P to the seedlings. Our results support the view that several Mycena species can associate closely with plant roots and some may potentially occupy a transitional state between saprotrophy and biotrophy.
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Affiliation(s)
- Ella Thoen
- Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316, Oslo, Norway
| | - Christoffer Bugge Harder
- Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316, Oslo, Norway
- Department of Plant and Soil Science, Texas Tech University, PO Box 42122, Lubbock, TX, 79409, USA
| | - Håvard Kauserud
- Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316, Oslo, Norway
| | - Synnøve S Botnen
- Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316, Oslo, Norway
| | - Unni Vik
- Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316, Oslo, Norway
| | - Andy F S Taylor
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
- The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, UK
| | - Audrius Menkis
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, PO Box 7026, SE-75007, Uppsala, Sweden
| | - Inger Skrede
- Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316, Oslo, Norway
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29
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Ectomycorrhizal Fungi: Participation in Nutrient Turnover and Community Assembly Pattern in Forest Ecosystems. FORESTS 2020. [DOI: 10.3390/f11040453] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Ectomycorrhizal fungi (EcMF) are involved in soil nutrient cycling in forest ecosystems. These fungi can promote the uptake of nutrients (e.g., nitrogen (N) and phosphorus (P)) and water by host plants, as well as facilitate host plant growth and resistance to stresses and diseases, thereby maintaining the aboveground primary productivity of forest ecosystems. Moreover, EcMF can acquire the carbon (C) sources needed for their growth from the host plants. The nutrient regulation mechanisms of EcMF mainly include the decay of soil organic matter via enzymatic degradation, nonenzymatic mechanism (Fenton chemistry), and priming effects, which in turn promote C and N cycling. At the same time, EcMF can secrete organic acids and phosphatases to improve the availability of soil P, or increase mycelium inputs to facilitate plant acquisition of P. The spatiotemporal distribution of EcMF is influenced by a combination of historical factors and contemporary environmental factors. The community of EcMF is associated with various factors, such as climate change, soil conditions, and host distribution. Under global climate change, investigating the relationships between the nutrient cycling functions of EcMF communities and their distribution patterns under various spatiotemporal scales is conducive to more accurate assessments of the ecological effects of EcMF on the sustainable development of forest.
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30
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Op De Beeck M, Troein C, Siregar S, Gentile L, Abbondanza G, Peterson C, Persson P, Tunlid A. Regulation of fungal decomposition at single-cell level. THE ISME JOURNAL 2020; 14:896-905. [PMID: 31896790 PMCID: PMC7082364 DOI: 10.1038/s41396-019-0583-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/11/2019] [Accepted: 12/18/2019] [Indexed: 11/13/2022]
Abstract
Filamentous fungi play a key role as decomposers in Earth's nutrient cycles. In soils, substrates are heterogeneously distributed in microenvironments. Hence, individual hyphae of a mycelium may experience very different environmental conditions simultaneously. In the current work, we investigated how fungi cope with local environmental variations at single-cell level. We developed a method based on infrared spectroscopy that allows the direct, in-situ chemical imaging of the decomposition activity of individual hyphal tips. Colonies of the ectomycorrhizal Basidiomycete Paxillus involutus were grown on liquid media, while parts of colonies were allowed to colonize lignin patches. Oxidative decomposition of lignin by individual hyphae growing under different conditions was followed for a period of seven days. We identified two sub-populations of hyphal tips: one with low decomposition activity and one with much higher activity. Active cells secreted more extracellular polymeric substances and oxidized lignin more strongly. The ratio of active to inactive hyphae strongly depended on the environmental conditions in lignin patches, but was further mediated by the decomposition activity of entire mycelia. Phenotypic heterogeneity occurring between genetically identical hyphal tips may be an important strategy for filamentous fungi to cope with heterogeneous and constantly changing soil environments.
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Affiliation(s)
- Michiel Op De Beeck
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden.
| | - Carl Troein
- Department of Astronomy and Theoretical Physics, Computational Biology and Biological Physics, Lund University, Sölvegatan 14A, SE-223 62, Lund, Sweden
| | - Syahril Siregar
- Department of Astronomy and Theoretical Physics, Computational Biology and Biological Physics, Lund University, Sölvegatan 14A, SE-223 62, Lund, Sweden
| | - Luigi Gentile
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden
- Department of Chemistry and CSGI, University of Bari Aldo Moro, IT- 701 21, Bari, Italy
| | - Giuseppe Abbondanza
- Department of Physics, Synchrotron Radiation Research, Lund University, SE- 223 62, Lund, Sweden
| | - Carsten Peterson
- Department of Astronomy and Theoretical Physics, Computational Biology and Biological Physics, Lund University, Sölvegatan 14A, SE-223 62, Lund, Sweden
| | - Per Persson
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden
- Centre for Environmental and Climate Research (CEC), Lund University, Ecology Building, SE-223 62, Lund, Sweden
| | - Anders Tunlid
- Department of Biology, Microbial Ecology Group, Lund University, Ecology Building, SE-223 62, Lund, Sweden
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Stuart EK, Plett KL. Digging Deeper: In Search of the Mechanisms of Carbon and Nitrogen Exchange in Ectomycorrhizal Symbioses. FRONTIERS IN PLANT SCIENCE 2020; 10:1658. [PMID: 31993064 PMCID: PMC6971170 DOI: 10.3389/fpls.2019.01658] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/25/2019] [Indexed: 05/12/2023]
Abstract
Symbiosis with ectomycorrhizal (ECM) fungi is an advantageous partnership for trees in nutrient-limited environments. Ectomycorrhizal fungi colonize the roots of their hosts and improve their access to nutrients, usually nitrogen (N) and, in exchange, trees deliver a significant portion of their photosynthetic carbon (C) to the fungi. This nutrient exchange affects key soil processes and nutrient cycling, as well as plant health, and is therefore central to forest ecosystem functioning. Due to their ecological importance, there is a need to more accurately understand ECM fungal mediated C and N movement within forest ecosystems such that we can better model and predict their role in soil processes both now and under future climate scenarios. There are a number of hurdles that we must overcome, however, before this is achievable such as understanding how the evolutionary history of ECM fungi and their inter- and intra- species variability affect their function. Further, there is currently no generally accepted universal mechanism that appears to govern the flux of nutrients between fungal and plant partners. Here, we consider the current state of knowledge on N acquisition and transport by ECM fungi and how C and N exchange may be related or affected by environmental conditions such as N availability. We emphasize the role that modern genomic analysis, molecular biology techniques and more comprehensive and standardized experimental designs may have in bringing cohesion to the numerous ecological studies in this area and assist us in better understanding this important symbiosis. These approaches will help to build unified models of nutrient exchange and develop diagnostic tools to study these fungi at various scales and environments.
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Affiliation(s)
| | - Krista L. Plett
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
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Frey SD. Mycorrhizal Fungi as Mediators of Soil Organic Matter Dynamics. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2019. [DOI: 10.1146/annurev-ecolsys-110617-062331] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Inhabiting the interface between plant roots and soil, mycorrhizal fungi play a unique but underappreciated role in soil organic matter (SOM) dynamics. Their hyphae provide an efficient mechanism for distributing plant carbon throughout the soil, facilitating its deposition into soil pores and onto mineral surfaces, where it can be protected from microbial attack. Mycorrhizal exudates and dead tissues contribute to the microbial necromass pool now known to play a dominant role in SOM formation and stabilization. While mycorrhizal fungi lack the genetic capacity to act as saprotrophs, they use several strategies to access nutrients locked in SOM and thereby promote its decay, including direct enzymatic breakdown, oxidation via Fenton chemistry, and stimulation of heterotrophic microorganisms through carbon provision to the rhizosphere. An additional mechanism, competition with free-living saprotrophs, potentially suppresses SOM decomposition, leading to its accumulation. How these various nutrient acquisition strategies differentially influence SOM formation, stabilization, and loss is an area of critical research need.
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Affiliation(s)
- Serita D. Frey
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire 03824, USA
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Sietiö OM, Santalahti M, Putkinen A, Adamczyk S, Sun H, Heinonsalo J. Restriction of plant roots in boreal forest organic soils affects the microbial community but does not change the dominance from ectomycorrhizal to saprotrophic fungi. FEMS Microbiol Ecol 2019; 95:5554003. [DOI: 10.1093/femsec/fiz133] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 08/22/2019] [Indexed: 12/17/2022] Open
Abstract
ABSTRACT
Boreal forest soils store significant amounts of carbon and are cohabited by saprotrophic and ectomycorrhizal fungi (ECM). The ‘Gadgil effect’ implies antagonistic interactions between saprotrophic fungi and ECM. Plant photosynthates support the competitive fitness of the ECM, and may also shape the soil bacterial communities. Many ‘Gadgil effect’ experiments have focused on litter layer (OL) or have litter and root-fragments present, and thus possibly favor the saprotrophs. We compared how the restriction of plant roots and exudates affect soil microbial community structures in organic soil (mixed OF and OH). For this, we established a 3-yr field experiment with 3 different mesh treatments affecting the penetration of plant roots and external fungal hyphae. Exclusion of plant photosynthates induced modest changes in both fungal and bacterial community structures, but not to potential functionality of the microbial community. The microbial community was resilient towards rather short-term disturbances. Contrary to the ‘Gadgil effect’, mesh treatments restricting the entrance of plant roots and external fungal hyphae did not favor saprotrophs that originally inhabited the soil. Thus, we propose that different substrate preferences (fresh litter vs. fermented or humified soil), rather than antagonism, maintain the spatial separation of saprotrophs and mycorrhizal fungi in boreal forest soils.
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Affiliation(s)
- Outi-Maaria Sietiö
- Department of Microbiology, University of Helsinki, P.O.Box 56, FIN-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O.Box 27, FIN-00014 Helsinki, Finland
| | - Minna Santalahti
- Department of Microbiology, University of Helsinki, P.O.Box 56, FIN-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O.Box 27, FIN-00014 Helsinki, Finland
- Department of Agricultural Sciences, University of Helsinki, P.O.Box 56, FIN-00014 Helsinki, Finland
| | - Anuliina Putkinen
- Department of Microbiology, University of Helsinki, P.O.Box 56, FIN-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O.Box 27, FIN-00014 Helsinki, Finland
- Department of Agricultural Sciences, University of Helsinki, P.O.Box 56, FIN-00014 Helsinki, Finland
| | - Sylwia Adamczyk
- Natural Resources Institute Finland, P.O.Box 2, 00791 Helsinki, Finland
| | - Hui Sun
- Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, NO.159, Longpan Road, Nanjing, 210037, China
| | - Jussi Heinonsalo
- Department of Microbiology, University of Helsinki, P.O.Box 56, FIN-00014 Helsinki, Finland
- Institute for Atmospheric and Earth System Research/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O.Box 27, FIN-00014 Helsinki, Finland
- Finnish Meteorological Institute FMI, Climate System Research, P.O.Box 503, FIN-00101 Helsinki, Finland
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Smith GR, Wan J. Resource-ratio theory predicts mycorrhizal control of litter decomposition. THE NEW PHYTOLOGIST 2019; 223:1595-1606. [PMID: 31066058 DOI: 10.1111/nph.15884] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 02/24/2019] [Indexed: 05/27/2023]
Abstract
Ecosystems with ectomycorrhizal plants have high soil carbon : nitrogen ratios, but it is not clear why. The Gadgil effect, where competition between ectomycorrhizal and saprotrophic fungi for nitrogen slows litter decomposition, may increase soil carbon. However, experimental evidence for the Gadgil effect is equivocal. Here, we apply resource-ratio theory to assess whether interguild fungal competition for different forms of organic nitrogen can affect litter decomposition. We focus on variation in resource input ratios and fungal resource use traits, and evaluate our model's predictions by synthesizing prior experimental literature examining ectomycorrhizal effects on litter decomposition. In our model, resource input ratios determined whether ectomycorrhizal fungi suppressed saprotrophic fungi. Recalcitrant litter inputs favored the former over the latter, allowing the Gadgil effect only when such inputs predominated. Although ectomycorrhizal fungi did not always hamper litter decomposition, ectomycorrhizal nitrogen uptake always increased carbon : nitrogen ratios in litter. Our meta-analysis of empirical studies supports our theoretical results: ectomycorrhizal fungi appear to slow decomposition of leaf litter only in forests where litter inputs are highly recalcitrant. We thus find that the specific contribution of the Gadgil effect to high soil carbon : nitrogen ratios in ectomycorrhizal ecosystems may be smaller than predicted previously.
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Affiliation(s)
- Gabriel R Smith
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA, USA
| | - Joe Wan
- Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland
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Zak DR, Pellitier PT, Argiroff W, Castillo B, James TY, Nave LE, Averill C, Beidler KV, Bhatnagar J, Blesh J, Classen AT, Craig M, Fernandez CW, Gundersen P, Johansen R, Koide RT, Lilleskov EA, Lindahl BD, Nadelhoffer KJ, Phillips RP, Tunlid A. Exploring the role of ectomycorrhizal fungi in soil carbon dynamics. THE NEW PHYTOLOGIST 2019; 223:33-39. [PMID: 30636276 DOI: 10.1111/nph.15679] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 01/07/2019] [Indexed: 05/26/2023]
Abstract
The extent to which ectomycorrhizal (ECM) fungi enable plants to access organic nitrogen (N) bound in soil organic matter (SOM) and transfer this growth-limiting nutrient to their plant host, has important implications for our understanding of plant-fungal interactions, and the cycling and storage of carbon (C) and N in terrestrial ecosystems. Empirical evidence currently supports a range of perspectives, suggesting that ECM vary in their ability to provide their host with N bound in SOM, and that this capacity can both positively and negatively influence soil C storage. To help resolve the multiplicity of observations, we gathered a group of researchers to explore the role of ECM fungi in soil C dynamics, and propose new directions that hold promise to resolve competing hypotheses and contrasting observations. In this Viewpoint, we summarize these deliberations and identify areas of inquiry that hold promise for increasing our understanding of these fundamental and widespread plant symbionts and their role in ecosystem-level biogeochemistry.
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Affiliation(s)
- Donald R Zak
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Peter T Pellitier
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, 48109, USA
| | - WilliamA Argiroff
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Buck Castillo
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Timothy Y James
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Lucas E Nave
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Colin Averill
- Department of Earth and Environment, Boston University, Boston, MA, 02215, USA
| | - Kaitlyn V Beidler
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | | | - Jennifer Blesh
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Aimée T Classen
- The Rubenstein School of Environment & Natural Resources, University of Vermont, Burlington, VT, 05405, USA
- The Gund Institute for Environment, University of Vermont, Burlington, VT, 05405, USA
| | - Matthew Craig
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | | | - Per Gundersen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, DK-1711, Denmark
| | - Renee Johansen
- Los Alamos National Laboratory, Santa Fe, NM, 87545, USA
| | - Roger T Koide
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA
| | - Erik A Lilleskov
- US Forest Service, Northern Research Station, 410 Mac Innes Dr., Houghton, MI, 49931, USA
| | - Björn D Lindahl
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, SE-750 07, Sweden
| | - Knute J Nadelhoffer
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | | | - Anders Tunlid
- Department of Biology, Microbial Ecology Group, Lund University, Lund, SE-221 00, Sweden
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Wang T, Tian Z, Tunlid A, Persson P. Influence of Ammonium on Formation of Mineral-Associated Organic Carbon by an Ectomycorrhizal Fungus. Appl Environ Microbiol 2019; 85:e03007-18. [PMID: 30877120 PMCID: PMC6498167 DOI: 10.1128/aem.03007-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/08/2019] [Indexed: 11/20/2022] Open
Abstract
The interactions between dissolved organic matter (DOM) and mineral particles are critical for the stabilization of soil organic matter (SOM) in terrestrial ecosystems. The processing of DOM by ectomycorrhizal fungi contributes to the formation of mineral-stabilized SOM by two contrasting pathways: the extracellular transformation of DOM (ex vivo pathway) and the secretion of mineral-surface-reactive metabolites (in vivo pathway). In this study, we examined how changes in nitrogen (N) availability affected the formation of mineral-associated carbon (C) from these two pathways. DOM was extracted from forest soils. The processing of this DOM by the ectomycorrhizal fungus Paxillus involutus was examined in laboratory-scale studies with different levels of ammonium. At low levels of ammonium (i.e., under N-limited conditions), the DOM components were slightly oxidized, and fungal C metabolites with iron-reducing activity were secreted. Ammonium amendments decreased the amount of C metabolites, and no additional oxidation of the organic matter was detected. In contrast, the hydrolytic activity and the secretion of N-containing compounds increased, particularly when high levels of ammonium were added. Under these conditions, C, but not N, limited fungal growth. Although the overall production of mineral-associated organic C was not affected by ammonium concentrations, the observed shifts in the activities of the ex vivo and in vivo pathways affected the composition of organic matter adsorbed onto the mineral particles. Such changes will affect the properties of organic matter-mineral associations and, thus, ultimately, the stabilization of SOM.IMPORTANCE Nitrogen (N) availability plays a critical role in the cycling and storage of soil organic matter (SOM). However, large uncertainties remain in predicting the net effect of N addition on soil organic carbon (C) storage due to the complex interactions between organic matter, microbial activity, and mineral particles that determine the formation of stable SOM. Here, we attempted to disentangle the effects of ammonium on these interactions in controlled microcosm experiments including the ectomycorrhizal fungus P.involutus and dissolved organic matter extracted from forest soils. Increased ammonium levels affected the fungal processing of the organic material as well as the secretion of extracellular metabolites. Although ammonium additions did not increase the net production of mineral-adsorbed C, changes in the decomposition and secretion pathways altered the composition of the adsorbed organic matter. These changes may influence the properties of the organic matter-mineral associations and, thus, the stabilization of SOM.
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Affiliation(s)
- Tao Wang
- Department of Biology, Microbial Ecology Group, Lund University, Lund, Sweden
| | - Zhaomo Tian
- Department of Biology, Microbial Ecology Group, Lund University, Lund, Sweden
- Centre for Environmental and Climate Research, Lund University, Lund, Sweden
| | - Anders Tunlid
- Department of Biology, Microbial Ecology Group, Lund University, Lund, Sweden
| | - Per Persson
- Department of Biology, Microbial Ecology Group, Lund University, Lund, Sweden
- Centre for Environmental and Climate Research, Lund University, Lund, Sweden
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Raineri M, Lima E, Larroza M, Moreno MS, Mansilla MV, Pappalardo JS, Zysler RD. Interaction between natural magnetite sub-micrometric particles and the Fasciola hepatica egg: The role of the exposed surface area. Exp Parasitol 2019; 199:59-66. [PMID: 30825498 DOI: 10.1016/j.exppara.2019.02.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 02/12/2019] [Accepted: 02/16/2019] [Indexed: 11/29/2022]
Abstract
Fasciolosis is a zoonotic world widely distributed disease caused by the liver fluke Fasciola hepatica, which affects animals and occasionally humans. On the other hand, natural iron oxide particles like magnetite are commonly found in soils where they participate in a wide range of environmental processes like organic matter decomposition, the adsorption of ions and molecules, and chemical reactions that involve the participation of soil living microorganisms. Since Fasciola eggs become soil components after being released with the infected animal faeces, this study focused on the characterization of the natural interaction between natural sub-micrometric magnetite particles and F. hepatica eggs. Our results indicate that particle binding to the F. hepatica egg depends on the particle size and it is also related to the exposed surface area since any condition that favors particle agglomeration leads to the reduction of the particle-eggshell binding intensity. Interestingly, this binding was avoided when proteins or phosphate were incorporated to the incubation solution, but not after formaldehyde fixation of eggs. Finally, when eggs were exposed to an external magnet after being incubated with magnetite particles, they were attracted to it without particles being detached, indicating a strong type of bonding between them. Therefore, the results presented here give new insights in order to improve the possibility of harvesting F. hepatica eggs by using magnetic materials.
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Affiliation(s)
- Mariana Raineri
- Instituto de Nanociencia y Nanotecnología CNEA-CONICET, Centro Atómico Bariloche, Av. Bustillo 9500, 8400, San Carlos de Bariloche, Argentina; Centro Atómico Bariloche, Comisión Nacional de Energía Atómica (CNEA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. E. Bustillo 9500 (R8402AGP), San Carlos de Bariloche, Río Negro, Argentina.
| | - Enio Lima
- Instituto de Nanociencia y Nanotecnología CNEA-CONICET, Centro Atómico Bariloche, Av. Bustillo 9500, 8400, San Carlos de Bariloche, Argentina; Centro Atómico Bariloche, Comisión Nacional de Energía Atómica (CNEA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. E. Bustillo 9500 (R8402AGP), San Carlos de Bariloche, Río Negro, Argentina
| | - Marcela Larroza
- Instituto Nacional de Tecnología Agropecuaria (INTA), Estación Experimental Agropecuaria Bariloche, Grupo de Salud Animal. Bote Modesta, Victoria 4450, 8400, San Carlos de Bariloche, Argentina
| | - M Sergio Moreno
- Instituto de Nanociencia y Nanotecnología CNEA-CONICET, Centro Atómico Bariloche, Av. Bustillo 9500, 8400, San Carlos de Bariloche, Argentina; Centro Atómico Bariloche, Comisión Nacional de Energía Atómica (CNEA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. E. Bustillo 9500 (R8402AGP), San Carlos de Bariloche, Río Negro, Argentina
| | - Marcelo Vásquez Mansilla
- Instituto de Nanociencia y Nanotecnología CNEA-CONICET, Centro Atómico Bariloche, Av. Bustillo 9500, 8400, San Carlos de Bariloche, Argentina; Centro Atómico Bariloche, Comisión Nacional de Energía Atómica (CNEA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. E. Bustillo 9500 (R8402AGP), San Carlos de Bariloche, Río Negro, Argentina
| | - Juan Sebastián Pappalardo
- Instituto Nacional de Tecnología Agropecuaria (INTA), Estación Experimental Agropecuaria Bariloche, Grupo de Salud Animal. Bote Modesta, Victoria 4450, 8400, San Carlos de Bariloche, Argentina
| | - Roberto D Zysler
- Instituto de Nanociencia y Nanotecnología CNEA-CONICET, Centro Atómico Bariloche, Av. Bustillo 9500, 8400, San Carlos de Bariloche, Argentina; Centro Atómico Bariloche, Comisión Nacional de Energía Atómica (CNEA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. E. Bustillo 9500 (R8402AGP), San Carlos de Bariloche, Río Negro, Argentina
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Zhu N, Wang S, Tang C, Duan P, Yao L, Tang J, Wong PK, An T, Dionysiou DD, Wu Y. Protection Mechanisms of Periphytic Biofilm to Photocatalytic Nanoparticle Exposure. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:1585-1594. [PMID: 30614685 DOI: 10.1021/acs.est.8b04923] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Researchers are devoting great effort to combine photocatalytic nanoparticles (PNPs) with biological processes to create efficient environmental purification technologies (i.e., intimately coupled photobiocatalysis). However, little information is available to illuminate the responses of multispecies microbial aggregates against PNP exposure. Periphytic biofilm, as a model multispecies microbial aggregate, was exposed to three different PNPs (CdS, TiO2, and Fe2O3) under xenon lamp irradiation. There were no obvious toxic effects of PNP exposure on periphytic biofilm as biomass, chlorophyll content, and ATPase activity were not negatively impacted. Enhanced production of extracellular polymetric substances (EPS) is the most important protection mechanism of periphytic biofilm against PNPs exposure. Although PNP exposure produced extracellular superoxide radicals and caused intracellular reactive oxygen species (ROS) accumulation in periphytic biofilm, the interaction between EPS and PNPs could mitigate production of ROS while superoxide dismutase could alleviate biotic ROS accumulation in periphytic biofilm. The periphytic biofilms changed their community composition in the presence of PNPs by increasing the relative abundance of phototrophic and high nutrient metabolic microorganisms (families Chlamydomonadaceae, Cyanobacteriacea, Sphingobacteriales, and Xanthomonadaceae). This study provides insight into the protection mechanisms of microbial aggregates against simultaneous photogenerated and nanoparticle toxicity from PNPs.
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Affiliation(s)
- Ningyuan Zhu
- Zigui Ecological Station for Three Gorges Dam Project, State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Sciences, Chinese Academy of Sciences , 71 East Beijing Road , Nanjing 210008 , China
- Department of Chemical and Environmental Engineering (ChEE) , 705 Engineering Research Center, University of Cincinnati , Cincinnati , Ohio 45221-0012 , United States
- College of Resource and Environment , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Sichu Wang
- Zigui Ecological Station for Three Gorges Dam Project, State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Sciences, Chinese Academy of Sciences , 71 East Beijing Road , Nanjing 210008 , China
- College of Resource and Environment , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Cilai Tang
- College of Hydraulic & Environmental Engineering , China Three Gorges University , Yichang 443002 , China
| | - Pengfei Duan
- Collaborative Innovation Center of Water Security for Water Source, Region of Mid-line of South-to-North Diversion Project , Nanyang Normal University , Nanyang 473061 , China
| | - Lunguang Yao
- Collaborative Innovation Center of Water Security for Water Source, Region of Mid-line of South-to-North Diversion Project , Nanyang Normal University , Nanyang 473061 , China
| | - Jun Tang
- Zigui Ecological Station for Three Gorges Dam Project, State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Sciences, Chinese Academy of Sciences , 71 East Beijing Road , Nanjing 210008 , China
- College of Resource and Environment , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Po Keung Wong
- School of Life Sciences , The Chinese University of Hong Kong , Shatin , NT Hong Kong SAR , China
| | - Taicheng An
- Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control , Guangdong University of Technology , Guangzhou 510006 , China
| | - Dionysios D Dionysiou
- Department of Chemical and Environmental Engineering (ChEE) , 705 Engineering Research Center, University of Cincinnati , Cincinnati , Ohio 45221-0012 , United States
| | - Yonghong Wu
- Zigui Ecological Station for Three Gorges Dam Project, State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Sciences, Chinese Academy of Sciences , 71 East Beijing Road , Nanjing 210008 , China
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The soil organic matter decomposition mechanisms in ectomycorrhizal fungi are tuned for liberating soil organic nitrogen. ISME JOURNAL 2018; 13:977-988. [PMID: 30538275 PMCID: PMC6461840 DOI: 10.1038/s41396-018-0331-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 08/27/2018] [Accepted: 11/28/2018] [Indexed: 02/08/2023]
Abstract
Many trees form ectomycorrhizal symbiosis with fungi. During symbiosis, the tree roots supply sugar to the fungi in exchange for nitrogen, and this process is critical for the nitrogen and carbon cycles in forest ecosystems. However, the extents to which ectomycorrhizal fungi can liberate nitrogen and modify the soil organic matter and the mechanisms by which they do so remain unclear since they have lost many enzymes for litter decomposition that were present in their free-living, saprotrophic ancestors. Using time-series spectroscopy and transcriptomics, we examined the ability of two ectomycorrhizal fungi from two independently evolved ectomycorrhizal lineages to mobilize soil organic nitrogen. Both species oxidized the organic matter and accessed the organic nitrogen. The expression of those events was controlled by the availability of glucose and inorganic nitrogen. Despite those similarities, the decomposition mechanisms, including the type of genes involved as well as the patterns of their expression, differed markedly between the two species. Our results suggest that in agreement with their diverse evolutionary origins, ectomycorrhizal fungi use different decomposition mechanisms to access organic nitrogen entrapped in soil organic matter. The timing and magnitude of the expression of the decomposition activity can be controlled by the below-ground nitrogen quality and the above-ground carbon supply.
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